randtest

#!/usr/bin/env perl
# Copyright (c) 2008 Vsevolod Kozlov <zaba@thorium.homeunix.org>
# License: Public Domain.
#
# Tool for testing your beloved RNG.
# Usage:
#  randtest [-l <limit>] [-r <rounds>] [-R <rand() per round>]
#

use strict;
use warnings;
use vars qw|$VERSION|;
$VERSION='1.1';
use Getopt::Std;
$Getopt::Std::STANDARD_HELP_VERSION = 1;

my %options;
getopts('qR:r:l:', \%options);

my $limit = $options{l} || rand;
my $rounds = $options{r} || 1;
my $one_round = $options{R} || 100;
my $quiet = $options{q};
my $hits = 0;
my ($randval, $total, $i);
$| = 1; # Autoflush.

print ".", "-" x $one_round, ".\n" unless ($quiet);
for ($i = 0; $i < $rounds; ++$i)
{
	print "|" unless ($quiet);
	foreach (1..$one_round)
	{
		$randval = rand();
		if ($randval <= $limit)
		{
			print "." unless ($quiet);
			$hits++;
		} else {
			print " " unless ($quiet);
		}
		$total++;
	}
	print "|\n" unless ($quiet);
}
print "'", "-" x $one_round, "'\n\n" unless($quiet);

print "$total rand() calls ($one_round*$rounds)\n";
print $hits*100/$total . "% less or equal to $limit\n";